Ryno317

Hi everyone. My son and I are building up a SE Blocks Flyer that we found neglected.

1) We need to replace the bottom bracket and I'm unsure what size or type we need. When we pulled the old one out, the one side was still on the spindle and I had to tap it to get the bearing's off.

2) Rear brakes, unsure what length lever arms.

Thanks

cbrstar

I'm pretty sure it's a Euro bottom bracket. Are you looking to replace the whole crank or just the bearings? If it's just the bearings they often have a number on the side of them and you can usually pick them up cheaper at a auto store compared to a bike shop. The brake levers are all personal choice for length. I looked it up and they use cheapo Promax. I'd just find one that looks cool and matches how you are fixing up the bike.

Rolla

2018-2020 Blocks Flyers had a Euro bottom bracket; 2021s have a Mid. If the bearing threads into the frame it's Euro. If the bearings press directly in, it's Mid. I believe all had/have a 19mm spindle.

Depending on year, the brakes were either Promax or Tektro V-brakes, so any V-brake lever should work. They spec them with a "2-finger" lever, if that matters.

If you figure out the year model, the SE Archives has many of the specs for each model. Look it up under the "Rad Series" of each year.

Ryno317

Thanks for the info so far.

Its 2019 based on the SN, so it would be a Euro BB.

What I ment on the length of the levers, was for the rear part where the brake pads mount. Maybe there called something different. But while shopping around I seen lengths of 85mm or 105mm. We have determined that we would need the longer one to clear the big tire (26x2.5).

My next question is about headsets. The current one is the caged ball bearing style and some of the ball bearings are missing from the bottom set. I would like to go to a sealed bearing type. I understand I would need to replace the cups and get a whole set. But I'm unsure of difference of 36 degree and 45 degree. I'm not sure what part that relates to, so that I could compare to the current set up. I have been looking at the FSA Orbit, is this do-able or what should I go with?

Thanks again.

Rolla

Since I assume you're going to have to press in the headset cups and replace the crown race, you'll want to do that at a bike shop, where they can help you get the right headset.

Pretty comprehensive headset info here: https://www.bikeradar.com/features/t...e-to-headsets/

Juan el Boricua

Here are the specs for the 2019 model; might help a bit.

Ryno317

Thanks for the Spec sheet. But it doesn't give me the specs for the Headset, just says Tange 1 1/8" threadless. pretty basic description.

cbrstar

You will have to pop out the cups of the old headset and measure the diameter of the lip that presses into the frame with a micrometer.

Juan el Boricua

https://www.bikeforums.net/bicycle-m...read-them.html

See if this helps if not, maybe call/write/email sebikes?

DMC707 

so just buy another Tange threadless headset. Simple

dont over complicate it, the SE’s are cheap and simple bikes (have had 3 of them over the years and currently have a Big Fler). They dont put anything exotic on them at all.

im just saddened that you found one only a year or so old that was so dogged out it needs all this , but kids can be abusive

Ryno317

I could, but to your point about kids being abusive to them. That's why I wanted to get a sealed bearing type, so it can last and be better protected from the elements. And yes this bike has been abused, my son will be the 3rd owner in the past 1-1/2 - 2 years. It had a rattle can paint job, none of the original stickers.(not stolen, I already checked the SN) I got it from a New Jersey shore town, so there was plenty of sand in the BB and headset bearings.

cbrstar

Were you able to measure the cups? On the Tange site the DX4 headsets state a outer diameter of 34mm but you should double check it. Tange makes a Technoglide in a similar size but it's pricey. You will have to google "Standard" 1 1/8th thread less headset. Other brands I can think of is FSA MX 1 1/8th but I'm sure there is others. Also check if your forks need a star nut and make sure that's included if you do. You might need to also order some spacers as the headset height might be different.